Lecture Notes on Technology and Design Decisions

Introduction

• Battery percentage on phones creates anxiety.
• Battery percentage is a complex lie rather than a simple measure.

How Battery Percentage Works

• Phones cannot directly measure battery level.
• Voltage Measurement: Changes depending on temperature and activity.
• Coulomb Counting: Counting energy input and output.
  • Starts at 100% and tracks energy flow.
  • Errors compound and create unreliability.
• Machine Learning: Predictive algorithms analyze usage over time to estimate discharge.

User Interface Design

Common Misconceptions

• iPhone Screen Shape: Not a simple rectangle, but a "squircle" (between circle and square).
• Spotify Shuffle: Not truly random; uses algorithms to avoid similar songs playing together.

Design Complexity

• Text navigation in editors is surprisingly complex due to varying letter widths.
• Implementing intuitive navigation can lead to counterintuitive user experiences.

Psychology in Design

Pull to Refresh

• Origin: Developed by Loren Brichter for Twitter (Tweety app).
• Intuitive gesture to refresh content, enhances engagement but can lead to addictive behaviors.

YouTube and Thumbnails

• New feature to filter videos by thumbnail color is seen as unnecessary and silly.

Google Maps Interface

• Zooming usually requires pinch gestures; double-tap and drag is a hidden feature.
  • Genius but lacks user affordance.

Keyboard Layouts

• QWERTY Keyboard: History rooted in typewriter design to avoid jams, not optimized for speed.
• Alternative layouts (Dvorak, Columac) exist but are not widely adopted due to QWERTY’s entrenched status.

Keyboard Modernization

• Modern apps are embracing keyboard shortcuts for efficiency (e.g., Raycast).
• Mouse usage is less efficient compared to keyboard shortcuts.

Legacy Keys on Keyboards

• Pause, Insert, and Scroll Lock: Remnants from the past with minimal current relevance.

Augmented and Virtual Reality Design

• Interfaces in VR/AR often have rounded corners to reduce perceived danger associated with sharp angles.
• Kiki and Booba experiment explains psychological associations with shapes.

Text Rendering Differences

• Mac vs. Windows text rendering: macOS opts for aesthetics while Windows focuses on legibility.
• Steve Jobs's influence led to better font presentation on Macs.

Conclusion

• Attention to detail in tech design can highlight underlying complexities.
• Technology's impact on happiness is more profound than simply being addictive.